Skill31 plottingpointsandintroto slope
- 1. Skills 31 Plotting Points on the Number Plane And introducing Slope of a line by plotting points Page 160 and following The test may have a problem where you just have to plot a (x,y) ordered pair. This should be an easy question. Look at the number plane below. The two intersecting lines meet at the point (0,0) which is the starting point of all graphing of points. The first number tells us to move left or right and pause to look at the second number which tells us to move up or down. It takes both numbers to plot one point. Study the examples below.
- 2. If you need more practice plotting points, try some of these in this puzzle. E. (2,1) Not on the line H. (-3, 2) R. (-5,0) E. (0, 03) N. (-2, -3) W. (2, -4) L. 5, -5)
- 3. Intro to Slope Slope is a number that describes the rate of change of a relationship. As you read this, we are experiencing the global pandemic with daily reports of how we are “flattening the curve.” What this means is that we are trying to change the slope of the curve. It is really, really important. We can figure out slope in several ways. Over the next few lessons, we will look at about 4 or 5 of them. To begin with, we will use slope = rise/run. The means we will count Up or down and then left or right as we go from point to point. Plot (1,2) and (4,4). I like to start at the lower point but you don’t have to. From (1,2) we have to go up 2 and then right 3. That means the slope is 2/3. Up is positive, down Is negative. Right is positive and left is negative. Plot (-4, -2) and (2, -5). Start at (2, -5). Head up 3 Lines and then move left 6) That means the slope is 3/-6 or simplified to -1/2. Practice the entire set of problems on page 163 In the book. The correct answers are all in the Boxes at the bottom of the page. This is really Important to understand the concept.
- 4. More practice on page 164. Find the slope of the lines drawn from point A to point B. From A for up 4 and right 3. Slope is 4/3 From B go 6 and left 3. Slope is 6/-3 Or -2/1 or just -2 From B go up 3 and left 5. Slope is 3/-5
- 5. A second important way to find slope using the slope formula. The slope formula is on the formula sheet. You do not have to memorize it. To use the formula, you do not need a graph. The problems for this are on page 164 at the middle. All answers are at the bottom in the boxes. If you don’t get one of the answers, you have made a mistake. Find the slope of the line passing through the two given points. Label the x and y values as (x1, y1) and (x2, y2). Then put them in the formula Slope is 3 – 1 which is 2/3. 5-2 Slope is 4-1 or 3 -7 - -3 -4 You can use your calculator on this to subtract. Use it. 1. 10.
- 6. Practice all the problems on page 164 in the book. Next time,we will continue learning about slope.